Background UK and US military personnel appear to have different health profiles yet direct comparisons of health status and deployment exposures between US and UK military populations have never been performed. Aims To compare US and UK military personnel deployed to the 1991 Persian Gulf War (PGW) for rates of symptom reporting, medical conditions and health status [Short Form-36 general health perception (GHP) and physical functioning (PF) subscales] and self-report military exposures. Methods We analysed representative cross-sectional samples of military personnel from the Iowa Persian Gulf Study (n = 3626) and the UK Health Survey of Military Personnel (n = 5573) that included directly comparable measures and stratified by those who had been deployed to PGW and those who had not been deployed to PGW. Results Although UK veterans had similar mean PF scores as US veterans (mean differences in PGW: 0.86, 95% CI -0.36 to 2.07 and in non-deployed -0.61, 95% CI -1.84 to 0.62), they had worse mean GHP scores (mean differences in PGW: -5.62, 95% CI -7.44 to -3.80 and in non-deployed -3.83, 95% CI -5.40 to -2.27). UK PGW veterans were more likely to report Gulf specific exposures, and this was associated with worse GHP(UK mean difference -9.05, 95% CI -11.49 to -6.61 versus US mean difference -4.30, 95% CI -6.62 to -1.98). Conclusions This study observed transatlantic variations in health status in military populations that may reflect cultural differences in the reporting of health.